webkit: disable on powerpc

webkit does not build correctly on powerpc. There is an upstream bug report
with a partial fix, but with remaining problems.
https://bugs.webkit.org/show_bug.cgi?id=113638

Until this problem is fixed, we disable webkit on powerpc.

Fixes
http://autobuild.buildroot.org/results/3ce/3ce992a663ddf1030a987bb778f8275a8e5fdef0/

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/webkit/Config.in

@@ -4,7 +4,9 @@ config BR2_PACKAGE_WEBKIT_ARCH_SUPPORTS
 	default y if (BR2_arm || BR2_armeb) && \
 		!(BR2_arm7tdmi || BR2_arm720t || BR2_arm920t || BR2_arm922t || BR2_fa526)
 	default y if BR2_i386 || BR2_mips || BR2_mipsel || \
-		BR2_powerpc || BR2_sh || BR2_sparc || BR2_x86_64
+		BR2_sh || BR2_sparc || BR2_x86_64
+
+# disabled on powerpc due to bug https://bugs.webkit.org/show_bug.cgi?id=113638
 
 config BR2_PACKAGE_WEBKIT
 	bool "webkit"